塔河油田深井穿盐膏层钻井液技术

深井盐膏层钻井施工风险极大,常会引起卡钻和套管损坏,影响安全钻井。通过对塔河油田深井盐膏层矿物组分、理化特征等进行综合分析,阐明井壁失稳的主要原因,为选择钻井液体系提供理论基础;对适应于该段的钻井液体系和现场维护处理技术进行了探索,提出了欠饱和盐水钻井液技术方案,并在T913井、TK827井、TK1106井进行了现场应用。结果表明,井下复杂大幅度降低,钻井周期大幅度缩短,经济效益较好。     

Enhancing sulphur self-retention by building-in CaO in straw–bitumen pellets

Combined straw–bitumen pellets have been proposed as an alternative fuel. An interesting finding is the potentiality of straw ash constituents to retain sulphur as bitumen that has relatively high sulphur content. The aim of the present work is to enhance sulphur self-retention to directly meet the environmental regulations by building-in CaO in the pellet instead of feeding sorbent separately. CaO powder has been mixed with the pellet constituents during production processes.     

Toward in-situ flaw detection in laser powder bed fusion additive manufacturing through layerwise imagery and machine learning

Process monitoring in additive manufacturing may allow components to be certified cheaply and rapidly and opens the possibility of healing defects, if detected. Here, neural networks (NNs) and convolutional neural networks (CNNs) are trained to detect flaws in layerwise images of a build, using labeled XCT data as a ground truth. Multiple images were recorded after each layer before and after recoating with various lighting conditions. Classifying networks were given a single image or multiple images of various lighting conditions for training and testing. CNNs demonstrated significantly better performance than NNs across all tasks. Furthermore, CNNs demonstrated improved generalizability, i.e., the ability to generalize to more diverse data than either the training or validation data sets. Specifically, CNNs trained on high-resolution layerwise images from one build showed minimal loss in performance when applied to data from an independent build, whereas the performance of the NNs degraded significantly. CNN accuracy was also demonstrated to be a function of flaw size, suggesting that smaller flaws may be produced by mechanisms that do not alter the surface morphology of the build plate. CNNs demonstrated accuracies of 93.5 % on large (>200 μm) flaws when testing and training on components from the same build and accuracies of 87.3 % when testing on a previously unseen build. Finally, evidence linking the formation of large lack-of-fusion defects to the presence of process ejecta is presented.     

Prediction of scouring around an arch-shaped bed sill using Neuro-Fuzzy model

In this study, Adaptive Neuro-Fuzzy Inference System (ANFIS) has been used to model local scouring depth and pattern scouring around concave and convex arch shaped circular bed sills. The experimental part of this research study includes seven sets of laboratory test cases which were performed in an experimental flume under different flow conditions. A data set consists of 2754 data points of scouring depth were collected to use in the ANFIS model. The ratio of arch diameter, D, to flume width, W, is used as a non dimensional variables in all test cases. The results from ANFIS model were compared with the results of ANN model obtained by Homayoon et al. [24] and previously presented models. The results indicated that for D/W equal to 1 and 1.2, the ANFIS models produced a good performance for convex and concave bed sills. As a result, the ANFIS models can be used as an alternative to ANN for estimation of scour depth and scour pattern around a concave bed sill installed with a bridge pier.     

Continuous size fractionation of magnetic nanoparticles by using simulated moving bed chromatography

The size fractionation of magnetic nanoparticles is a technical problem, which until today can only be solved with great effort. Nevertheless, there is an important demand for nanoparticles with sharp size distributions, for example for medical technology or sensor technology. Using magnetic chromatography, we show a promising method for fractionation of magnetic nanoparticles with respect to their size and/or magnetic properties. This was achieved by passing magnetic nanoparticles through a packed bed of fine steel spheres with which they interact magnetically because single domain ferro-/ferrimagnetic nanoparticles show a spontaneous magnetization. Since the strength of this interaction is related to particle size, the principle is suitable for size fractionation. This concept was transferred into a continuous process in this work using a so-called simulated moving bed chromatography. Applying a suspension of magnetic nanoparticles within a size range from 20 to 120 nm, the process showed a separation sharpness of up to 0.52 with recovery rates of 100%. The continuous feed stream of magnetic nanoparticles could be fractionated with a space-time-yield of up to 5 mg/(L∙min). Due to the easy scalability of continuous chromatography, the process is a promising approach for the efficient fractionation of industrially relevant amounts of magnetic nanoparticles.     

近2年我国锆铪及锆化学制品雕生产、贸易及研发概况

介绍了我国近2年来海绵锆、锆铪制品和锆化学品的生产、进出口概况,以及重要研发进展。我国工业级海绵锆产量从2003年的100t增加到2005年的174t,2005年的销售量达到150t;锆粉与锆-铝消气剂等年产量在10t左右;锆材和锆设备年产量在100t以上;锆化学制品品种有10余种,年产量已达到20×104t。锆砂的沸腾氯化工艺、锆铪的MIBK法分离工艺、以电熔ZrO2为原料制取粗ZrCl2工艺和Al-Y复合ZrO2粉的生产工艺等的研发工作,都取得了突破性进展。     

TiN/SiNx submicronic multilayer coatings obtained by chemical vapor deposition in a fluidized bed reactor at atmospheric pressure (AP/FBR-CVD)

TiN/SiN_x multilayer coatings were deposited on stainless steel by Chemical Vapor Deposition in a Fluidized Bed Reactor at Atmospheric Pressure (AP/FBR-CVD) by reaction of TiCl₄ and SiCl₄ with NH₃ at 850 °C. Due to the immiscibility of crystalline TiN and amorphous SiN_x, interdiffusion between layers is avoided even at the high working temperature. The thickness of the individual layer was in the nanometer range. Coatings were characterized by means of SEM, TEM, GD-OES, SIMS, XRD and nanoindentation. A mechanism for the growth rate and diffusion of Ti and Si into the steel is discussed.     

浅谈流化床干燥器布风板的设计

介绍流化床干燥器所用各种形式布风板的结构。并对其使用情况作了分析。特别对高温布风板的形式进行了探讨。     

气流床水煤浆气化技术的应用现状及开发进展

气流床水煤浆气化是煤高效、洁净利用的一项关键技术。简述了具有代表性的气流床水煤浆气化技术的应用现状及开发进展,并分析了影响水煤浆气化的主要因素,如烧嘴、耐火砖、进料系统、激冷环等,提出了一些改进措施。     

Energy Aspects in Drying

The energy performance of a dryer and a drying process is characterized by various indices such as volumetric evaporation rate, steam consumption, unit heat consumption and energy (thermal) efficiency. Of all indices, energy efficiency is the most frequently quoted, in technical specifications. A thorough analysis of available information, including the Handbook of Industrial Drying, points to the inconsistency of terminology, definition and data interpretation. Thus, reported data on energy efficiency vary significantly and frequently contradict both drying theory and industrial practice. To establish a common platform to deal with energy issues, this article provides a concise overview of the most common definitions of energy efficiency, along with a critical review of the published data. A need for energy audit and benchmarking is pointed out. To eliminate shortcomings of the energy efficiency as a lumped parameter, and to allow analysis of energy consumption over time (batch drying) or distance (continuous drying), instantaneous and cumulative indices are proposed. Using these indices, the energy performance of selected dryers is examined, and possible modifications to dryer design and operating parameters are indicated in order to reduce the overall energy consumption.